1. Field of the Invention
This invention relates to hair spray resin compositions, and, more particularly, to aerosol and pump formulations which may contain a low amount of volatile organic compounds (VOC).
2. Description of the Prior Art
Effective hair spray formulations and film-forming resins must meet a rigid set of requirements. Specifically, the film-forming resins should remain non-tacky in a humid environment but be easily removed using soap solutions such as shampoos. The film should have high hair cohesivity and possess sufficient strength and elasticity so as to avoid dusting or flaking when the hair is subjected to combing or brushing stresses, and remain clear, transparent and glossy on aging. The film-forming resin should have a viscosity range which permits spraying without nozzle clogging, and should show little or no tendency to interact with perfumes or other optional components typically utilized in a hair spray formulation. The resin should also be readily soluble in various solvents while exhibiting good compatibility with conventional propellants such as hydrocarbons, dimethyl ether, or mixtures thereof.
Many polymeric systems have been developed in an attempt to meet these stringent requirements. Among these are polyvinylpyrrolidone and co-polymers of N-vinylpyrrolidone with vinyl acetate. However, these co-polymers do not exhibit the desired degree of holding under high humidity conditions. Moreover, several of the vinylpyrrolidone polymers possess an unpleasant odor. Methyl vinyl ether/maleic acid half ester co-polymers have also been used in hair sprays but these must be of a relatively high molecular weight to achieve adequate holding. Vinyl acetate polymers having 15 to 35 percent of their acetate groups converted to hydroxyl groups have been proposed for increased solubility in carbon dioxide propellant systems. However such increased solubility is achieved at the cost of lowered holding power. While each of the above resins meets at least some of the above cited requirements, none exhibits all of these characteristics to a satisfactory degree.
Chuang, in U.S. Pat. No. 4,689,379, described an improved hair fixative resin which was a terpolymer resin of random or alternating structure comprising a vinyl ester, a water-insoluble or water-miscible alkyl maleate half-ester and the acrylate or methacrylate ester of a saturated hydroxylated bicyclic hydrocarbon, in a molar ratio of about 1:0.35-1:0.05-0.25. The resin was prepared in the form of beads or microspheres by suspension polymerization to provide a higher molecular weight for better hair holding under humid conditions. These terpolymers were preferably composed of vinyl acetate, an alkyl maleate half-ester and acrylate and/or methacrylate esters of isoborneol, exo-norborneol and endonorborneol, with the isoborneol ester being most preferred.
Accordingly, it is an object of the present invention to provide new and improved hair spray resin compositions which can develop fine spray patterns in both aerosol and pump use, exhibits prolonged curl retention under humid conditions, good holding power, ease of removability, and resistance to polymer build-up.
Other hair spray compositions, both aerosol and pump spray formulations, are described in detail in U.S. Pat. Nos. 3,145,147; 4,223,009; 4,521,402, and 4,859,455.
However, these and other pump formulations available in the art contain a considerable amount of alcohol which is a volatile organic compound (VOC). Aerosol hair spray formulations also require hydrocarbons or other propellants which add to the VOC content of the composition. Recent state legislation, moreover, has required that hair spray compositions have a lower VOC level than is presently found in commercial hairspray compositions. More particularly, it is now necessary that such compositions contain VOC materials at a weight level of no more than 80% of the composition.
Accordingly, it is another object of the present invention to provide new hair spray compositions which meet VOC standards while retaining the effective properties of presently available compositions for hair preparation and treatment.
Another object of the invention is to provide hair spray resin compositions capable of providing a fine finishing mist at a high resin solids level and which is substantially moisture resistant, also forms a stiff resin film on the hair of the user, and provides a good hold and curl retention, and which composition has a substantially reduced VOC level, particularly a lower alcohol concentration in pump formulations, and, a low level of alcohol and propellant components in aerosol-based formulations.
These and other objects and features of the invention will be made apparent from the following more particular description thereof.